new here, need some diesel help

[1-bad-burb]

first off, Hi, I'm Parker, I'm from west virginia, I'm 16 and just bought my first vehicle, a 1985 diesel suburban, I'm pretty mechanically inclined, not compared to some of u guys though , I bought this sub and I love it, but I got some major issues wth it, some have been takin care of but others leave me stumped, heres the details on the truck: 1985 suburban, 6.2 diesel, 2 1/2" flowmaster exhaust, k&n filter, thats all the mods to the engine, 6" all spring superlift susp. lift, 35" goodyear wrangler MT's, 15" eaton monster wheels, 4l60E tranny rebuilt with a TCI master racing overhaul kit and shift kit (dont know any details about it, I didnt do the work or have it done, just bought it that way) 3:73 gears (gotta replace em, 0-60 in about 30 sec's down hill just aint gonna work) I've read all 8 pages in the diesel forum and it helped me fix a couple things ok so heres my questions that hopefully a couple of you guys can answer:

this thing is a pain to get started, it has 160,000 miles and runs great, once its started it runs 160 degrees with around 65 -75 psi, I would rether stab myself in the foot then start it on a cool morning, I have installed quick heat glow plugs from ssdieselsupply and that didnt help a bit, it has a newer starter that seems to spin it over pretty good, and the truck pushes out a little black smoke so I guess the IP is healthy, the previous owner didnt feel like replaceing the fuel lift pump so he installed an electrical one that is hanging in a dangerous spot by one zip tie also he left the lift pump where it was with the lines disconnected and the holes for the fuel lines are all open, the GP controller seems to work fine, it comes on for about 8 seconds, give or take a couple, goes off, comes on for a second goes off, etc, etc, the motor will start, and after about 2 seconds it will die, then the first or second crank after that it will fire right up and keep on running problem free the high idle works fine and goes off when it should, I realy cant figure this out, I'm stumped, I love my diesel but if it keeps on going like this im going to be burning up starters like crazy, I've looked at the 28mt and if this one gives out from the continues cranking I'll replace it with one of those, but this starter spins it over pretty fast


well, im too tired and too slow of a typer to list my couple other problems right now, but if I can fix the one listed above it would realy help me out and ease my mind.



thanks in advance for your help guys

 

[83-6.5TD-BURB]

i have an 82, when mine did that it was the glowplugs. maybe one side of the gp circ is not getting juiced. don't know if the setup on all of em has a left/right fused link but one might be out, try putting a test light to all of the gp's. mine are manual control so thats a lot easier. also a buddy of mine didn't get his water drain on the primary all the way tight one time, not loose enough to leak when you look at it but over night it would drip enough to make it a pain to start, might check for that type of pronlem too, where in the sys is your lift pump. i went with an electric as weel and i have mine, tank-pump-primary-secondary-ip that way i have no trouble pumping air out of the sys, at least to the secondary filter. does yours have the funky multi purpose filter/heater/water sensor thing on the firewall or just the primary filter. the gizmo is well known for letting air in. just get a regular primary and check it for water often and ditch the gizmo. also it WILL suck in air and NOT leak fuel at that thing.

 

[tRustyK5]

The stalling is the clue you should be focussing on. I've never had my 6.2 stall once it's started...ever. I would guess you probably have the model 80 filter/fuel heater on the firewall...and it's likely cheating a little air into the fuel system.

With quick heats and 'approx' 8 seconds of initial glow time I don't think you have any GP worries. Those GP's get to glowing red in 5 seconds...

A diesel is compression ignition, so once the thing starts there isn't much that will make it stall. The injection pump send each individual injector a little pressure spike of fuel in sequence. All it takes is one small blip of air going to the injection pump and it'll kill the motor dead...because instead of being able to send the pressure spike, the air in the system compresses and sends the injector nothing.

I run a Racor and a spin on filter and have never had any trouble with them at all.

If you do still have the model 80 filter I'd recomend swapping it out for something more reliable.

Rene

 

[1-bad-burb]

thanks for your help guys, that makes sence I'm gonna replace the filter, what would you all reccomend to get rid of the current one? I think it is the model 80 if thats the big rectangular one on the firewall. with the lift pump still attached to the motor with the holes for the lines open will that cause me any problems? should I plug the holes?? I'm also gonna test the glow plugs just for the heck of it, I have a test light, do I just stick it inbetween the glow plug and the wire running to it and then cycle the plugs?



thanks, Parker

 

[diesel4me]

glow plug tests

To check the glow plugs themselves,hook a test lamp to the + battery terminal,and touch the other end to a disconnected glow plug--it should light the lamp it the glow plug is good--to check the power coming into the glow plugs,unplug them and hook the test light to ground,and probe each green wire with the key "ON" but with the engine not running--you should have juice at all 8 leads...

I'd ditch the rectangular style filter for one that has a water drain and a spin on style filter..those style always let air leak in,and caused hard starting..my 82 has the spin on style,but I'm not sure if its factory for that year--someone might have swapped it off a later truck before I bought it..

My 82 K20 has a universal electric fuel pump in the fuel line,PLUS the OEM lift pump--I leave the electric pump on anytime the engine is running(its wired to the "on" position of the ignition)...mine starts much faster and easier with it energized...yours might not even be running if its hanging by zip ties,and isn't grounded to the frame somehow!..

Also might want to check the fuel shutoff solenoid in the injector pump--make sure its got 12V when the key is on,and try touching the wire to its terminal and listen for a "click",to mak sure its opening and letting fuel get to the injector pump..

I'd also check every rubber hose from the tank to the injector pump--my truck had about 20 ft of rubber hoses,manual tank switching valves,etc..it was a mess!--I chopped it all off,and ran all new hoses and replaced a few feet of rusty metal lines,and I only run 1 of my dual tanks (other one leaks!,so I disconnected all the hoses from it--probably take it out someday)..it starts EVERY time qiuckly now,even if it sits for weeks!--I had to crank it until the batteries nearly died when I first got it,or use WD-40 to coax it to life.--I also put in a manual pushbutton switch for the glowplugs,I used AC G60 glowplugs...its like night and day now!

 

[steve_kibbe]

I bet your 82 came with the spin on filter, my 83 has a spin on. When I baught my truck it had a aux electric pump. After a year or so it quit but the truck ran fine. I have another one for when I get my motor back in it though.

 

[jarheadk5]

OK, is this the Model 80 filter everyone seems to hate?

 

[1-bad-burb]

yepp, thats the one I gotim hoping to get it replaced on my next day off (monday) that realy makes sence now, about the filter leaking air into my fuel system, I'm glad the truck never sits for more then 24 hours without being started or it would probrably have to be bled lol




this is definatly the best 4X4 forum EVER

 

[tRustyK5]

That would be the one...prone to leaking in behind the filter apparently. Not so much as you'd notice, but just enough to let a bit of air in.

Supposed to be a common problem, i wouldn't know first hand.

Rene

 

[jarheadk5]

Thank you, gentlemen. There'll be a new thread in the Diesel forum re: filtration if anyone wants to chime in...

{Note to self: don't re-use old filter assy.}